颜色度量因子耦合局部特征聚类的 图像复制-粘贴篡改检测算法

针对当前较多图像复制-粘贴篡改检测算法主要依靠图像的灰度信息来检测图像特征,没有考虑图像的色彩特征,使其存在误检与漏检的不足,引入余弦调制高斯滤波(cosine modulated Gaussian,CMG),设计了基于颜色度量因子与局部特征聚类的图像复制-粘贴篡改检测算法。利用CMG来求取图像的尺度响应值,并通过极值计算来提取图像的候选特征点;再利用像素点的光谱反射模型来建立颜色度量因子,从候选特征点中确定图像的鲁棒特征点。构建特征点的邻域圆,并求取该圆域中的四元数指数矩(quaternion exponent moments,QEM),从而得到相应的特征向量;利用特征向量来计算特征点间的欧氏距离,完成图像的特征匹配。最后,利用匹配点对的R、G、B值,形成特征点的局部特征,实现图像特征的聚类,准确定位复制-粘贴伪造内容。仿真结果显示,较当前的复制-粘贴伪造检测方法而言,对于简单的复制-粘贴篡改和复杂组合篡改,所提方法都具备更高的检测精度与鲁棒性。

Image forgery detection algorithm based on color metric factor coupled local feature clustering

At present, many image duplication paste tampering detection algorithms mainly rely on the gray level information of the image to detect image features, but do not consider the color factor of the image, resulting in the deficiency of error detection and missing detection in the detection results. Based on cosine modulated Gauss filtering, an image copy paste tampering detection algorithm based on color metric factor coupled with local feature clustering is designed in this paper. The CMG is used to obtain the scale response value of the image, and the candidate feature points are extracted by the extremum calculation. The spectral reflection model of the pixels is used to establish the color measurement factor, which is used to determine the image feature points from the candidate feature points. The neighborhood circle of the feature points is constructed and the quaternion exponential moments in the circle are obtained to form the feature vectors. The Euclidean distance between feature points is calculated by using eigenvectors to complete image feature matching. By using the R, G and B values of matching point pairs, the local features of feature points are formed, the clustering of image features is completed, the forgery content is located and copied and pasted, and the tampering detection results are obtained. The simulation results show that compared with the current copy paste forgery detection method, the proposed method has higher detection accuracy and robustness for simple copy paste forgery and complex combination forgery.